It has become common practice to fasten sheet metal and like objects together by use of a special rivet which is provided with a separable mandrel. The rivet itself is a hollow element through which extends a nail-like mandrel. When pressure is brought on top of the rivet while pulling on the mandrel the rivet collapses, thus forming the rivet on either side of the elements to be fastened together. The mandrel breaks and is no longer associated with the rivet. A number of tools have been developed for performing this function of setting the rivet, but they have all been quite expensive and complicated. Furthermore, they have not been completely successful, since they have required extremely large pressing forces to operate them. They have been subject to a number of disabilities due to being complicated and difficult to maintain in operating condition. Furthermore, most designs involve an exit port out of which the mandrel is driven as the tool operates. The necessary location of that exit port is in a place where the operator might accidently apply pressure with his hand. As a result, the mandrel may be driven into the operators hand. In addition, the operation of some rivet setters can result in the unexpected expulsion of the broken mandrel from the exit port with sufficient velocity to be dangerous to an operator who is not using sufficient care. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a rivet setting tool of simple, rugged construction.
Another object of this invention is the provision of a rivet setting tool which is inexpensive to manufacture.
A further object of the present invention is the provision of a rivet setting tool which requires a minimum of maintenance.
It is another object of the instant invention to provide a rivet setting tool which does not require large amounts of energy to operate.
It is a further object of the invention to provide a rivet setting tool which eliminates the possibility that the mandrel will be unexpectedly expelled from the tool.
A still further object of the invention is the provision of a rivet setting tool which is simple in construction, inexpensive to manufacture, and which is capable of a long life of useful service with a minimum of maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.